• Title/Summary/Keyword: forensic science

Search Result 454, Processing Time 0.029 seconds

Choosing Optimal STR Markers for Quality Assurance of Distributed Biomaterials in Biobanking

  • Chung, Tae-Hoon;Lee, Hee-Jung;Lee, Mi-Hee;Jeon, Jae-Pil;Kim, Ki-Sang;Han, Bok-Ghee
    • Genomics & Informatics
    • /
    • v.7 no.1
    • /
    • pp.32-37
    • /
    • 2009
  • The quality assurance (QA) is of utmost importance in biobanks when archived biomaterials are distributed to biomedical researchers. For sample authentication and cross-contamination detection, the two fundamental elements of QA, STR genotyping is usually utilized. However, the incorporated number of STR markers is highly redundant for biobanking purposes, resulting in time and cost inefficiency. An index to measure the cross-contamination detection capability of an STR marker, the mixture probability (MP), was developed. MP as well as other forensic parameters for STR markers was validated using STR genotyping data on 2328 normal Koreans with the commercial AmpFlSTR kit. For Koreans, 7 STR marker (D2S1338, FGA, D18S51, D8S1179, D13S317, D21S11, vWA) set was sufficient to provide discrimination power of ${\sim}10^{-10}$ and cross-contamination detection probability of ${sim}1$. Interestingly, similar marker sets were obtained from African Americans, Caucasian Americans, and Hispanic Americans under the same level of discrimination power. Only a small subset of commonly used STR markers is sufficient for QA purposes in biobanks. A procedure for selecting optimal STR markers is outlined using STR genotyping results from normal Korean population.

Rapid Diagnosis of CMT1A Duplications and HNPP Deletions by Multiplex Microsatellite PCR

  • Choi, Byung-Ok;Kim, Joonki;Lee, Kyung Lyong;Yu, Jin Seok;Hwang, Jung Hee;Chung, Ki Wha
    • Molecules and Cells
    • /
    • v.23 no.1
    • /
    • pp.39-48
    • /
    • 2007
  • Charcot-Marie-Tooth (CMT) disease and hereditary neuropathy with liability to pressure palsies (HNPP) are frequent forms of genetically heterogeneous peripheral neuropathies. Reciprocal unequal crossover between flanking CMT1A-REPs on chromosome 17p11.2-p12 is a major cause of CMT type 1A (CMT1A) and HNPP. The importance of a sensitive and rapid method for identifying the CMT1A duplication and HNPP deletion is being emphasized. In the present study, we established a molecular diagnostic method for the CMT1A duplication and HNPP deletion based on hexaplex PCR of 6 microsatellite markers (D17S921, D17S9B, D17S9A, D17S918, D17S4A and D17S2230). The method is highly time-, cost- and sample-saving because the six markers are amplified by a single PCR reaction and resolved with a single capillary in 3 h. Several statistical and forensic estimates indicated that most of these markers are likely to be useful for diagnosing the peripheral neuropathies. Reproducibility, as determined by concordance between independent tests, was estimated to be 100%. The likelihood that genotypes of all six markers are homozygous in randomly selected individuals was calculated to be $1.6{\times}10^{-4}$, which indicates that the statistical error rate for this diagnosis of HNPP deletion is only 0.016%.

The complete mitochondrial genome sequence of the indigenous I pig (Sus scrofa) in Vietnam

  • Nguyen, Hieu Duc;Bui, Tuan Anh;Nguyen, Phuong Thanh;Kim, Oanh Thi Phuong;Vo, Thuy Thi Bich
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.30 no.7
    • /
    • pp.930-937
    • /
    • 2017
  • Objective: The I pig is a long nurtured longstanding breed in Vietnam, and contains excellent indigenous genetic resources. However, after 1970s, I pig breeds have become a small population because of decreasing farming areas and increasing pressure from foreign breeds with a high growth rate. Thus, there is now the risk of the disappearance of the I pigs breed. The aim of this study was to focus on classifying and identifying the I pig genetic origin and supplying molecular makers for conservation activities. Methods: This study sequenced the complete mitochondrial genome and used the sequencing result to analyze the phylogenetic relationship of I pig with Asian and European domestic pigs and wild boars. The full sequence was annotated and predicted the secondary tRNA. Results: The total length of I pig mitochondrial genome (accession number KX094894) was 16,731 base pairs, comprised two rRNA (12S and 16S), 22 tRNA and 13 mRNA genes. The annotation structures were not different from other pig breeds. Some component indexes as AT content, GC, and AT skew were counted, in which AT content (60.09%) was smaller than other pigs. We built the phylogenetic trees from full sequence and D loop sequence using Bayesian method. The result showed that I pig, Banna mini, wild boar (WB) Vietnam and WB Hainan or WB Korea, WB Japan were a cluster. They were a group within the Asian clade distinct from Chinese pigs and other Asian breeds in both phylogenetic trees (0.0004 and 0.0057, respectively). Conclusion: These results were similar to previous phylogenic study in Vietnamese pig and showed the genetic distinctness of I pig with other Asian domestic pigs.

Menadione Induced Apoptosis in MKN45 Cells via Down-regulation of Survivin (Menadione의 Survivin 하향 조절을 통한 MKN45 세포의 세포사멸 유도 효과)

  • Lee, Min Ho;Kim, Jeongyong;Cho, Yoonjung;Kim, Do Hyun;Yang, Ji Yeong;Kwon, Hye Jin;Park, Min;Woo, Hyun Jun;Kim, Sa-Hyun;Kim, Jong-Bae
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.51 no.1
    • /
    • pp.71-77
    • /
    • 2019
  • Menadione is known as an anti-tumor factor. Many studies have reported the potential anti-cancer role of menadione against a range of cancer cell lines. In this study, the anti-cancer effects of menadione and the underlying molecular signaling involved in apoptosis was investigated in gastric cancer cell lines. The menadione treatment decreased the cell viability of MKN45 gastric cancer cells. The decreased cell viability was attributed to the induction of apoptosis, which was confirmed by the results indicating the activation of caspase-3 and -7 and the cleavage of PARP in Western blotting. The upstream regulatory molecules involved in apoptosis were investigated further and it was discovered that menadione reduced the expression of survivin, an inhibitor of upstream apoptosis proteins. In addition, a transcription factor ${\beta}$-catenin, which is known to regulate survivin expression, was down-regulated by menadione. A previous report showed that menadione inhibited XIAP expression to induce apoptosis and induced G2/M cell cycle arrest in AGS cells. This study elucidated another inhibitory mechanism of menadione against gastric cancer cells in a different cell line. Although further studies will be needed, the inhibitory mechanism demonstrated in this study will help better understand the anti-cancer effects of menadione.

The comparative study of two extraction methods for ancient DNA: silica suspension method and ultracentrifugal concentrator method (고대 유전자에 대한 두 종류의 DNA 분리 방법의 비교 연구: 실리카 현탁액 방법 및 초원심분리 농축 방법)

  • Lee, Eun-jung;Maixner, Frank;Zink, Albert
    • Analytical Science and Technology
    • /
    • v.31 no.2
    • /
    • pp.65-70
    • /
    • 2018
  • This study compared two methods for preparing ancient DNA (aDNA) for the construction of successful shotgun libraries that may be applied to massive parallel sequencing. For the comparative analysis, the DNA of prehistoric rib samples from Hungary was extracted using either a manually prepared silica suspension or the Amicon Ultracel-15 10K ultracentrifugal device (Millipore). After the extraction of the same amount of bone powder (about 150 mg) from three samples by each method, the amount of extracted double-stranded DNA and the subsequent degree of construction of the shotgun library were analyzed. The Amicon device method was rapid and easier to perform and resulted in an approximately 11-fold higher DNA recovery than that obtained using the silica suspension. The shotgun library constructed using DNA templates prepared by the Amicon device was more successful than that constructed from templates isolated using the silica suspension. The comparative study of these two aDNA extraction methods showed that the Amicon device has the advantages of saving time, process simplicity, and high efficiency.

Regression model for the preparation of calibration curve in the quantitative LC-MS/MS analysis of urinary methamphetamine, amphetamine and 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid using R (소변 중 메트암페타민, 암페타민 및 대마 대사체 LC-MS/MS 정량분석에서 검량선 작성을 위한 R을 활용한 회귀모델 선택)

  • Kim, Jin Young;Shin, Dong Won
    • Analytical Science and Technology
    • /
    • v.34 no.6
    • /
    • pp.241-250
    • /
    • 2021
  • Calibration curves are essential in quantitative methods and for improving the accuracy of analyte measurements in biological samples. In this study, a statistical analysis model built in the R language (The R Foundation for Statistical Computing) was used to identify a set of weighting factors and regression models based on a stepwise selection criteria. An LC-MS/MS method was used to detect the presence of urinary methamphetamine, amphetamine, and 11-nor-9-carboxy-Δ9 -tetrahydrocannabinol in a sample set. Weighting factors for the calibration curves were derived by calculating the heteroscedasticity of the measurements, where the presence of heteroscedasticity was determined via variance tests. The optimal regression model and weighting factor were chosen according to the sum of the absolute percentage relative error. Subsequently, the order of the regression model was calculated using a partial variance test. The proposed statistical analysis tool facilitated selection of the optimal calibration model and detection of methamphetamine, amphetamine, and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol in urine. Thus, this study for the selection of weighting and the use of a complex regression equation may provide insights for linear and quadratic regressions in analytical and bioanalytical measurements.

A comparative analysis of metadata structures and attributes of Samsung smartphone voice recording files for forensic use (법과학적 활용을 위한 삼성 스마트폰 음성 녹음 파일의 메타데이터 구조 및 속성 비교 분석 연구)

  • Ahn, Seo-Yeong;Ryu, Se-Hui;Kim, Kyung-Wha;Hong, Ki-Hyung
    • Phonetics and Speech Sciences
    • /
    • v.14 no.3
    • /
    • pp.103-112
    • /
    • 2022
  • Due to the popularization of smartphones, most of the recorded speech files submitted as evidence of recent crimes are produced by smartphones, and the integrity (forgery) of the submitted speech files based on smartphones is emerging as a major issue in the investigation and trial process. Samsung smartphones with the highest domestic market share are distributed with built-in speech recording applications that can record calls and voice, and can edit recorded speech. Unlike editing through third-party speech (audio) applications, editing by their own builtin speech applications has a high similarity to the original file in metadata structures and attributes, so more precise analysis techniques need to prove integrity. In this study, we constructed a speech file metadata database for speech files (original files) recorded by 34 Samsung smartphones and edited speech files edited by their built-in speech recording applications. We analyzed by comparing the metadata structures and attributes of the original files to their edited ones. As a result, we found significant metadata differences between the original speech files and the edited ones.

Hot Corrosion and Thermally Grown Oxide Formation on the Coating of Used IN738LC Gas Turbine Blade (사용된 IN738LC 가스 터빈 블레이드 코팅층의 고온 부식 및 Thermally Grown Oxide 형성 거동)

  • Choe, Byung Hak;Han, Sung Hee;Kim, Dae Hyun;Ahn, Jong Kee;Lee, Jae Hyun;Choi, Kwang Su
    • Korean Journal of Materials Research
    • /
    • v.32 no.4
    • /
    • pp.200-209
    • /
    • 2022
  • In this study, defects generated in the YSZ coating layer of the IN738LC turbine blade are investigated using an optical microscope and SEM/EDS. The blade YSZ coating layer is composed of a Y-Zr component top coat layer and a Co component bond coat layer. A large amount of Cr/Ni component that diffused from the base is also measured in the bond coat. The blade hot corrosion is concentrated on the surface of the concave part, accompanied by separation of the coating layer due to the concentration of combustion gas collisions here. In the top coating layer of the blade, cracks occur in the vertical and horizontal directions, along with pits in the top coating layer. Combustion gas components such as Na and S are contained inside the pits and cracks, so it is considered that the pits/cracks are caused by the corrosion of the combustion gases. Also, a thermally grown oxide (TGO) layer of several ㎛ thick composed of Al oxide is observed between the top coat and the bond coat, and a similar inner TGO with a thickness of several ㎛ is also observed between the bond coat and the matrix. A PFZ (precipitate free zone) deficient in γ' (Ni3Al) forms as a band around the TGO, in which the Al component is integrated. Although TGO can resist high temperature corrosion of the top coat, it should also be considered that if its shape is irregular and contains pore defects, it may degrade the blade high temperature creep properties. Compositional and microstructural analysis results for high-temperature corrosion and TGO defects in the blade coating layer used at high temperatures are expected to be applied to sound YSZ coating and blade design technology.

Survey of Work Experiences and Practices of Occupational Therapists in the Mental Health Field: A Focus on Physical Function Enhancement Interventions (정신건강 분야에서 근무하는 작업치료사의 업무 경험 및 실태조사: 신체기능 향상 중재를 중심으로)

  • Kim, Min-Jee;Kim, Young-wook;Kim, Jun-hyeok;Kim, Ga-hee;Choi, Hong-seok;Moon, Kwangtae
    • Therapeutic Science for Rehabilitation
    • /
    • v.12 no.4
    • /
    • pp.53-65
    • /
    • 2023
  • Objective : This study aimed to identify the experiences and practices of occupational therapists in mental health and provide interventions for improving body function in individuals with mental illness. Methods : Data were collected from mental health therapists between November 7 and November 14, 2022. A survey was distributed via email and 46 responses were analyzed using descriptive statistics and correlations. Results : The majority were female (58.7%), aged 20-30 years (84.8%), working in mental health centers (41.3%), and undergoing mental health occupational therapy training (91.3%). They had 1-3 years of mental health experience (65.2%) and were commonly involved in programs (71.1%), case management (62.2%), and administration (57.8%). Interventions for physical functioning were common (73.9%), including group interventions (41.2%), such as stretching, aerobic exercise, and walk training, and individual interventions (38.1%), such as walking, stretching, and aerobic exercise. Conclusion : Occupational therapists play a crucial role in enabling individuals with mental illness to engage in daily life activities. However, relevant studies in this field are lacking. This study emphasizes the importance of mental health occupational therapy and the need for evidence-based services for physical function improvement interventions to provide more effective treatments for mental illnesses.

Improving the Efficiency of the EWF-file Imaging Time from a Cryptographic Perspective (암호학적 관점에서의 EWF 파일 이미징 효율성 개선 방안 연구)

  • Shin, Yonghak;Kim, Dowon;Lee, Changhoon;Kim, Jongsung
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.26 no.4
    • /
    • pp.911-919
    • /
    • 2016
  • Compared to the past, the current disk storages have dramatically increased and extremely many data are transferred on the network everyday. In spite of the anticipation that such development will be continued, there have been lack of studies for improving the data-imaging time in terms of the digital forensics. In this paper, we firstly investigate the time due to hash functions during the data Imaging and secondly propose a method for improving the efficiency of the EWF-File imaging time from a cryptographic perspective.